Characterisation of particle size distribution in Adeno-Associated Viral Vectors (AAVs) by Dynamic Light Scattering (DLS)
Adeno-associated viral vectors (AAVs) are small (~20-25 nm), non-enveloped viruses involved in the development of gene therapy protocols for the treatment of various diseases. Their ability to contain DNA sequences is of interest for various therapeutic applications and the absence of any viral genes has proven to be one of the safest strategies. The control of their size as well as their arrangement in sample solutions are important parameters to consider in the development of their use in gene therapies.
Dynamic Light Scattering (DLS) is a non-destructive spectroscopic analysis technique giving access to the size of particles in suspension in a liquid, typically for particles with diameters between 1 nm and 3 µm. The particle size measured in a DLS instrument is the diameter of the sphere that scatters at the same speed as the particle being measured. The particles in a liquid move randomly and their movement speed is used to determine the size of the particle. In a liquid, particles are constantly moving where small particles move faster than large ones. Taking two pictures of a sample solution separated by a short time interval shows how much particles have moved. The more the particles have moved, the smaller they are and vice versa. The ability of DLS to determine the particle size distribution provides an opportunity to observe the possible different population sizes of AAV samples.
The aim of this study is to develop a method for the size determination of AAV samples by DLS. This application note presents the development of the method as well as the evaluation of method performance. The results demonstrate the good performance of the method in terms of precision and robustness. The method can be used for the routine determination of the size distribution of AAV samples.
In addition to this application note,
Claire Butré, R&D Technical Leader, guides your through this application note in the below video